The Indian Space Research Organisation has successfully test-fired its indigenously developed upper stage for 50s at its Liquid Propulsion Systems Centre at Mahendragiri, southern India. The engine will replace the Russian-supplied upper stage for India's three-stage Geosynchronous Satellite Launch Vehicle (GSLV). The GLSV is designed to orbit India's Insat-class spacecraft, which weighs more than 2,000kg (4,400lb). The maiden flight of the Indian upper stage on a GSLV booster is set for next year.